To boost or not to boost, that is the question.

[Glorishears]

It's very situational, which was probably their intent - it's a more strategic game is there's no one right answer to the question.

Runners: in a runner v. Runner battle - e.g. the top of Long Nine - boost, because it's a decisive advantage against other runners. When spamming their base, don't boost, because it only takes one hit from a bigger unit to kill anyway.

Soldiers: I tend to boost, because there's usually a heavy or a sniper around and not being a one-hit kill is good. But if you're the attacker, yea, four unboosted can kill two out of three boosted; vis versa three boosted will only kill one out of four unboosted. A mix of boosted soldiers + unboosted runners works well, especially if you can arrange it that the runners take the counterattack first.

Heavies: The main reason not to boost a heavy is that you've already spent almost all your wits that turn making it and moving it off your base. But on defense having something that can't be killed by two soldiers is awesome, and having more instead isn't quite the same given their limited mobility.